4000mAh Extended Battery With Back Cover For Blackberry Z10 Description: Compatible Brand: For Blackberry Z10 Capacity: 4000mAh 3.7VDC Battery type: Lithium-ion polymer battery Note: you need to use this Thick Battery with the back cover. this battery is not suitable for BlackBerry's Porsche-designed Z10 P'9982 Package included: 1 x 4000mAh Replacement Battery 1 x Back Cover